computer networks

A computer network is a collection of two or more computers with communication between them through a medium. The communication medium can be through radio waves
wires
infrared
optical fibers etc.

Computer network is an integral part of our daily lives
with the most important reason being that of communication. The use of computer networking is to share resources like fax machines
printers
modems
files etc.
and its other uses are database server
computer server
email
chat
internet etc. The computer to which the resources are attached is called the server and the other computers that access the resource are called clients. In peer-to-peer computer networks there are no servers.

The sharing of fax machines
printers
and modems amongst many computers and users reduce the operational cost. A database on a computer network is a very important application as it stores and runs many important data and jobs. Emails and chats can be used for instantaneous communication and sending of files on a computer network.

The computer networks are classified
depending upon the size
as Local Area Networks (LAN)
Wide Area Networks (WAN)
Metropolitan Area Networks (MAN) and Personal Area Networks (PAN). The topology (topology is the way the computer networks and network resources are connected) of the networking can be classified as Bus Network
Ring Network and Star Network.

The networking hardware basically consists of wiring
network cards and a hub. Computer network cards are required so that one computer can understand what the other computer is “talking”. Network cards have a unique MAC address to identify computers on a computer network. Hubs connect all the computers in the network. Hubs can also be used to connect to other hubs to increase the size of the computer network. Two computers can be connected using Ethernet cards or phone lines or power lines for communication
with hardware kits available at roughly a cost of $100.

As the number of computers in an office or a home increases
so do the number of cables
so wireless networking is a viable solution. In wireless networking radio transreceivers or infrared signals are used to communicate between computers and devices. Examples of wireless networking include Wi-fi and Bluetooth technology
though there may be security issues involved in wireless networking. However there definitely is a stronger preference towards wireless networking nowadays among consumers.

Computer networks have added a new dimension to the 21st century. Today the cyber world is much faster and wider than the real world. This has all been made possible due to computer networks. Computer networks have revolutionized business
communication
travel
research
defense
society and almost all human endeavors. The evolution of computer networks has helped the technological revolution take a big leap forward.

Today it is almost inconceivable for a business not to have computers
whether it is a construction company or a high technology firm. When a business has more than one computer
they are almost always connected together in a local area network. These networks may be more or less advanced and therefore more or less costly.

Companies invest so much (in terms of both money and time) in a local area networks because there are many advantages that a local area network brings to a business and how it is administered.

Some businesses use a local area network in such a way they are highly dependent on it always working. If the company's network fails
then you may see all the employees chatting away in the corridors because they can't do their work. This means big losses for the company and causes stresses on the employees. All companies must consider their local area networks a vital asset and downtime must be avoided. This imposes huge demands on the network staff to keep such networks running almost 100% of the time.


The advantages of Computer Network Management

One of the main advantages of installing and maintaining LANs is the opportunity they create for better communication and cooperation between employees and customers.

Security considerations: Local Area Network security can be both a help and hindrance. Comprehensive security is beneficial because it provides a central and safe strategy for data access and disaster recovery. All information is protected by the design and implementation of the network security solution. On the other hand
interconnecting computers in local area networks creates a security risk
since doing so makes it technically possible for intruders to access many machines on the network at once.

Cost considerations: Installing a local area network is a relatively expensive project. Servers
cabling
switches
routers and software can all be expensive and should never be purchased without expert advice. Keeping the network operating and secure also requires a lot of resources and can be costly.

Surprisingly
a local area network can bring a number of cost savings. Sharing resources avoids the need to purchase equipment for each individual. Even more important is the security that a local area network can provide. Data loss could cost a business a great deal of money and in some cases
cause the business to shutdown altogether. Computer Network Management should require a consistent routine for data backups with regular checkups of data quality - a practice that will save a company huge sums in the event of a mishap.


Computer Network Management: preliminary analysis phases

The first phase of computer network management is to determine the source of the problem (a preliminary study that looks into several options of differing scope may be useful here) and defining it in a specification of requirements. Examples of what should be evaluated are different network operating systems
mail systems
and other applications. The choice of hardware components should also be evaluated. This phase is generally aimed at establishing what the system should do
not how it should do it.


Computer Network Management: design phase

The purpose of design phase is to determine how the requirements of the specification are to be met. The current approach to large
complex projects is to break them down into smaller
more manageable subprojects.


Computer Network Management: implementation phase

This phase involves the physical installation of the local area network. Cables are run
software is installed
and computers and other hardware are put in place.


Computer Network Management: integration and system testing phase

In this phase
commissioning of the network begins
and routines are adapted to users and the operating personnel. The system must be tested
both to ensure that the network meets the requirements set out in the specification and that it is stable enough to perform the central function it has in the organization.


Computer Network Management: operation and maintenance

Local area networks have complex operating routines. This is because there may be serious consequences when faults occur or unauthorized persons gain access to the system. Many companies have employees devoted solely to take care of running and maintaining computer networks. These system administrators may deal with network issues such as performance
reliability and security of both hardware and software.


Computer Network Management: tools

Although an organization may have computer administrators on site
they must also monitor the network more than eight hours a day. In fact
some of the worst trouble that arises with networks can happen during the night hours when nobody is using the network. With the right computer network management tools
your organization can receive the security of knowing that problems will be foreseen
prevented
and taken care of - and that your network administrator can be notified at a moment's notice
should anything go exceptionally wrong.

Do you own or manage a computer consulting company? Are you having trouble growing your computer consulting company's profits?

If so
then you must learn how to focus on your computer consulting firm's profit and bottom line.

In this article
we'll look at 7 profit secrets and strategies you can use in your computer consulting business
to ensure that you are able to balance your clients' small business IT needs against your own computer consulting company's profitability challenges.

Origins of the Problem

While focusing on your computer consulting profits may sound simple enough at first glance
this business-focused discipline often eludes many a computer consulting firm.

This usually happens because many computer consulting business owners fall in love the technology gadgetry
and get seduced by seemingly attractive reseller channel programs
at the expense of their business' profit.

At the end of the day however
your computer consulting company is a business… not a charity and not a hobby. And your computer consulting company must be run like a business.

Profit Secret #1: Show motivation with your small business computer consulting clients.
To avoid being labeled as just another clueless geek
you need to position your computer consulting services to be more in line with those of a virtual CIO for hire. So always be on the look out for new ways to enhance your clients' businesses… not just fix broken desktops and servers.

Profit Secret #2: Be dedicated to the task and relentless in your pursuit to improve the status quo.
Because it takes a lot of work to land the best computer consulting clients
you need to focus on lifetime customer value… not just one-shot-deal sales. So always remember that your proposed or recently implemented computer consulting technology solution isn't a one-shot deal. This kind of long-term vision and planning requires tremendous staying power and perseverance… which often escapes many computer consulting business owners.

Profit Secret #3: Don't be afraid to be creative with your client engagements.
Small business technology solutions often need to stay within relatively modest budgets. And your computer consulting solutions must work without the need for in-house IT staff. To satisfy these challenges
don't be afraid to think outside of the box when appropriate.

Profit Secret #4: Evaluate how your clients' systems
both paper- and computer-based
function today.
As part of your virtual CIO role
look at how these existing clients systems are meeting or not meeting present and future needs. Most of this work will be done during IT audits… another key computer consulting profit secret that can really help to separate you from the pack of mediocrity.

Profit Secret #5: Put yourself in your clients' shoes and think about what THEIR clients need from them.
Yes
as a computer consulting business owner
you need to have good people skills and a certain degree of empathy for your clients' business problems. But an even more advanced computer consulting business owner doesn't just stop at understanding their clients' business problems. The virtual CIO really digs in and learns about their clients' customers' business problems… one layer down on the value chain.

Profit Secret #6: Keep up with advances and new versions.
As virtual CIO for your computer consulting clients
your clients depend on your firm to advise them on what tools can better help their businesses grow. So while you can't allow this R&D and training to consume and devour all of your scarce weekly schedule
you do need to stay a few steps ahead of your clients' IT needs at all times.

Profit Secret #7: Summarize and share that information with your clients.
The essence of your R&D and training should focus on one major objective: will this new platform or tool add value to your computer consulting clients' existing or future installations? And how you can best summarize this information
in layperson language that non-technical clients can understand?


The Bottom Line
Your computer consulting firm's needs to be your client's virtual IT department can often be at odds with your computer consulting firm's need to be profitable. A big part of this problem happens because computer consulting business owners fall in love with technology
at the expense of their marketing and sales activities.

To make sure you don't fall into this same strap
which can kill your computer consulting profits
don't go overboard with your training and R&D activities. Be sure to keep business development activities in your weekly schedule… EVERY week. If you want to keep your computer consulting profits as healthy as possible
make sure that you're proactive in your marketing and sales activities… dig the well for computer consulting profits BEFORE you're thirsty. And a great way to start is by listening to the profit-generating secrets at http://www.computer-consulting-101.com


Copyright MMI-MMVI
Small Biz Tech Talk Blog. All Worldwide Rights Reserved. {Attention Publishers: Live hyperlink in author resource box required for copyright compliance}

Do you own or manage a computer consulting company? Would you like to achieve greater small business success? If so
then get ready to learn why most computer consulting companies get IT (Information Technology) wrong and what you can do about IT.

The Problem: Why Most Computer Consulting Companies Get IT Wrong

Most owners of computer consulting companies make their jobs much harder than need be. Why? Because these computer consulting business owners fall in love with the technology… and view their small business clients as a distant second priority.

However
if you get this part of “IT” wrong
you will doom your computer consulting company to “clueless geek” status. It's crucial that you understand one extremely important principle here: Recruiting and retaining small business clients is your #1 computer consulting priority. Keeping up with IT should never get in the way of the mission of your computer consulting company.

In other words
don't get seduced by the hardware
operating systems or applications. Fall-in-love with the business opportunities surrounding how you solve your clients' biggest business problems with your recommended IT solutions. That's the real mission of a computer consulting company.

The Solution: Blend Computer Consulting and Virtual IT

To put this all in perspective with your computer consulting company
you need to understand and embrace the concept of virtual IT.

Virtual IT is what allows your computer consulting company to function as an extension of your small business clients' companies. Your computer consulting company essentially becomes the outsourced IT department for your small business clients.

As owner or manager of a computer consulting company in this role
you will most likely become the de facto CIO (chief information officer)
CTO (chief technology officer)
or IT manager for your small business clients.

And just like any well-rounded internal IT department
your virtual IT computer consulting business will need to provide
or arrange for
a complete soup-to-nuts solution that includes services like help desk
desktop support
network administration
engineering
security
training
procurement
and asset management… because anything short of the complete virtual IT solution will leave valuable computer consulting money on the table.


The Bottom Line

Most computer consulting companies are making a huge mistake when it comes to their small business engagements… because these computer consulting business owners fall-in-love with the technology
at the expense of the business opportunities. In order for your computer consulting company to flourish
make sure that you understand the concept of virtual IT and build virtual IT into every major business decision for your computer consulting company. To continue learning more about how you can use virtual IT to grow your computer consulting company
go sign-up right now for the one-hour free training seminar on 5 Easy Ways to Grow Your Computer Consulting Business at http://www.ComputerConsultingBusiness.com

Copyright MMI-MMVI
Computer Consultants Secrets .com
All Worldwide Rights Reserved. {Attention Publishers: Live hyperlink in author resource box required for copyright compliance}

San Francisco
California October 10
2006
Following a lackluster Q3
Cisco Systems emerges as the leader in the 10 Gigabit Ethernet Switch Market for the fourth quarter. Fueled by increased demand and an overall rise in the average selling price
Cisco experienced significant gains in a market of over $300 Million.

With almost 70% of the projected $1.3 Billion 10-Gig market share and a more powerful
yet affordable design
the Catalyst 6500 is poised to cement Cisco as the dominating force in the industry. With the recent release of an eight-port
10
Ethernet module for the 6500
Cisco is quickly pulling away from the rest of the pack.

In addition
upgrades like the Application Control Engine (ACE) module have prompted companies like Pure Video Networks to adopt Cisco switches to manage traffic of their popular video websites. Implementing simultaneous data center services such as server load balancing
integrated network and application switching/security
the ACE module delivers the highest performance in the industry. The ACE Simplifies application infrastructure by combining the functionality of multiple application delivery appliances into a single module
including server load balancing and off-load
Secure Socket Layer (SSL) protocol
security
and application optimization capabilities.

Already the most successful networking switch on the IT market
the 6500 Series reduces existing operational costs and improves a network's ability to respond to intensive bandwidth demands. In general
customers using the services modules for the Catalyst 6500 reduce their total cost of ownership by taking advantage of simplified infrastructure
improved investment protection
pervasive security
and the high levels of performance
scalability
and innovative technologies.

With over twenty unique service modules in five distinct categories
the Catalyst 6500 ranks among the most scalable
high-performance platform for integrated services. Currently
Cisco offers modules that address security issues
application
networking
network monitoring
wireless/mobility
and IP communications
which can be integrated into existing catalyst switches. Each modules offers upgraded performance and reinforces Cisco's hold on the market for network switches. With more than $20 Billion is sales sine it's release in 1999
the 6500 Series switch has become the most popular networking platform ever.

While Cisco has been able to fend off most threats to their position
rival Foundry Networks
and newcomer Force 10 have recently launched new 10Gbe ready products aimed at disrupting the company's market share. According to literature on Force 10's Terascale E-Series 1200
the E1200 boasts of more than double the ports of the Catalyst 6500 (1260 vs. 576 Ethernet ports/chassis). While this may be good news for the company
Force 10 has been focused on the data center vertical
and is therefore still untested in the enterprise market. Foundry's BigIron RX series switch has received favorable press for it's size/performance ratio and lower prices. With the launch of the new RX series
Foundry has mounted a consistent affront to Cisco's unchallenged reign.

Even with the competition mounting new efforts
the Cisco name is still a major factor among IT professionals whose networks depend on their equipment. Fortunately for the stalwart Cisco
reputation is still the key to market dominance.

Today's bandwidth expectations mean that Category 5 is strategically dead. The Category 5 Enhanced (5e) standards
which should have been ratified in August and may be finalized at November's committee meeting
specify new measurements that provide more margins for 100BaseTX and ATM-155 traffic. Critically
Category 5e standards make reliable Gigabit Ethernet connections possible. But many structured cabling suppliers argue that Category 5e is only an interim solution on the road to Category 6
which will support at least 200 MHz; in the interests of sufficient operating margin
the IEEE is requesting a 250-MHz Category 6 specification. Despite the fact that the Category 6 standards are only at draft stage
manufacturers are offering a host of products and claiming that these products comply with the draft proposals.
What is a category 6 cable? Out of the three cable categories (Cat-5
Cat-5e & Cat-6)
Category 6 is the most advanced and provides the best performance. Just like Cat 5 and Cat 5e
Category 6 cable is typically made up of four twisted pairs of copper wire
but its capabilities far exceed those of other cable types because of one particular structural difference: a longitudinal separator. This separator isolates each of the four pairs of twisted wire from the others
which reduces crosstalk
allows for faster data transfer
and gives Category 6 cable twice the bandwidth of Cat 5! Cat 6 cable is ideal for supporting 10 Gigabit Ethernet
and is able to operate at up to 250 MHz. Since technology and standards are constantly evolving
Cat 6 is the wisest choice of cable when taking any possible future updates to your network into consideration. Not only is Category 6 cable future-safe
it is also backward-compatible with any previously-existing Cat 5 and Cat 5e cabling found in older installations.
Category 6
(ANSI/TIA/EIA-568-B.2-1) is a cable standard for Gigabit Ethernet and other network protocols that is backward compatible with the Category 5
category 5e and Category 3 cable standards. Cat-6 features more stringent specifications for crosstalk and system noise. The cable standard is suitable for 10BASE-T / 100BASE-TX and 1000BASE-T (Gigabit Ethernet) and is expected to suit the 10000BASE-T (10Gigabit Ethernet) standards. It provides performance of up to 250 MHz.
The cable contains four twisted copper wire pairs
just like earlier copper cable standards. Although Cat-6 is sometimes made with 23 gauge wire
this is not a requirement; the ANSI/TIA-568-B.2-1 specification states the cable may be made with 22 to 24 AWG gauge wire
so long as the cable meets the specified testing standards. When used as a patch cable
Cat-6 is normally terminated in 8P8C often incorrectly referred to as “RJ-45" electrical connectors. Some Cat-6 cables are too large and may be difficult to attach to 8P8C connectors without a special modular piece and are technically not standard compliant. If components of the various cable standards are intermixed
the performance of the signal path will be limited to that of the lowest category. As with all cables defined by TIA/EIA-568-B
the maximum allowed length of a Cat-6 horizontal cable is 90 meters (295 feet). A complete channel (horizontal cable plus cords on either end) is allowed to be up to 100 meters in length
depending upon the ratio of cord length: horizontal cable length.
The cable is terminated in either the T568A scheme or the T568B scheme. It doesn't make any difference which is used
as they are both straight through (pin 1 to 1
pin 2 to 2
etc). Mixed cable types should not be connected in serial
as the impedance per pair differs and would cause signal degradation. To connect two Ethernet units of the same type (PC to PC
or hub to hub
for example) a cross over cable should be used
though some modern hardware can use either type of cable automatically.
Return loss measures the ratio of reflected-to-transmitted signal strength and is the single most difficult test to repeat with consistent results; at Category 6 levels
the difference between a pass and a fail can be the amount of bend in a test cord. Return loss is also causing headaches for connector manufacturers
because the RJ-45 system isn't up to the job. The final stumbling block with Category 5e ratification concerns the RJ-45 hardware; Category 6 is committed to RJ-45 for backward compatibility
but the ISO's proposed Category 7 system will have a new and as-yet-unspecified connector to accompany its revised cabling. Today
the return loss problem explains why manufacturers of Category 6 hardware
which is supposed to be interoperable
claim Category 6 performance only if you use the manufacturers' matched parts throughout a channel link.
The Telecommunications Industry Association (TIA) is working to complete a new specification that will define enhanced performance standards for unshielded twisted pair cable systems. Draft specification ANSI/TIA/EIA-568-B.2-10 specifies cable systems
called "Augmented Category 6" or more frequently as "Category 6a"
that operates at frequencies up to 500 MHz and will provide up to 10 Gbit/s bandwidth. The new specification has limits on alien crosstalk in cabling systems.
Augmented Category 6 specifies cable operating at minimum frequency of 500 MHz
for both shielded and unshielded. It can support future 10 Gb/s applications up to the maximum distance of 100 meters on a 4-connector channel.

Cabling your home for computer network - still a requirement?

With proliferation of wireless networking and communication equipment it is oh-so-tempting to cut the cord and save a significant sum of money in the process. But is everything that a regular computer networking user needs can be done using just wireless network? Let’s take a look at some pros and contras:

1. One important advantage of having a cabled network is the available bandwidth or simply speed. At the present point in time the speed of connection via a simple and inexpensive CAT5E cable can be 1000Mbit/sec
whereas the best that IEEE802.11g (one of the many flavors of Wi-Fi) can offer is only 54Mbit/sec. It may not seem so significant if you think you are only browsing Internet
and the DSL speed available to you is 1.5Mbit/sec. However
if you need to print via your network connection on a remote printer
you should realize that the print jobs
depending on the amount of graphic data in them
can easily reach dozens and even hundreds megabytes. Since 1Byte=8bit one 100MByte print job will take 15 seconds (and in reality this time can be much longer) to transmit via a Wi-Fi wireless connection
and this time shrinks to mere 1 sec or less on wired 1000MBit/s Ethernet connection. Same principal applies to transferring files
backing up files on other computers in the network etc.
2. It is not possible today and with all probability will not be possible in the future to transmit power needed for your networking device via the wireless link. Unless
of course
you would be willing to be subjected to very high levels of microwave radiation. Thus a device that was marketed to you as “un-tethered” will in fact be very much tethered via the power cord or will have to be re-charged every so often. The power requirements are increasingly important for devices that are expected to be always online
such as phone sets. Therefore it is best to have it connected via a cable that can deliver both power and the communication signal at the same time.
3. Wireless communications are very much proprietary and require whole gamut of conversion equipment to transmit multi-media signals. The same CAT5E cable can without any modification support phone
computer network
balanced line level audio signal
baseband video signal as well as host of other
more specialized
control applications’ signals. With inexpensive adapters called “baluns” the same cable can carry significant number of channels of broadband television or carry a baseband video
such as security camera output
through great distances. All of those applications
except the computer network of course
will require specialized expensive conversion equipment if they needed to be transmitted via a Wi-Fi link.
4. The cost benefit of not running wires around the house is not as simple as issue as it seems. Having installed a wireless network at home you have only eliminated the need to wire for a single application – computer network. A modern home
however
requires all kinds of wiring to run even without regard to computers. The power and phones are obvious examples
as well as thermostats and security systems. Pre-wired speakers are common and most homes today have intercom systems as a desirable option
and those also require extensive wiring. It is very likely that the same contractor running the intercom or security cables is qualified to run computer cables – CAT5E or better. If you are building a home
you should definitely check if computer cabling option is available in your new home
and our advice is to go ahead and purchase it before the walls close. It is going to be a pretty involved and expensive procedure to install the cables later. As an added cost benefit of a wired computer network you will find that all modern computers ship with wired Ethernet network interface card included
and the latest models ship with 1000MBit/sec cards that are essentially free for the computer’s owner.

There are multiple sources of information available on proper planning and design of a residential cabling for voice
data
audio
video and other applications. One of the best sources is the TIA/EIA-570B standard
most resent release of which has been published in 2004. The standard outlines recommended types of the cables
principals of cable distribution in a single- and multi-dwelling units as well as recommended amount of cables to be installed based on the size of the house.

In conclusion
cutting the wire seems like a step forward
some sort of liberation of computer from the bonds of the infrastructure. I would caution the reader
however
to take a more balanced and informed approach before joining the wireless revolution. There are still (and will remain in foreseen future) sound reasons to include properly designed cabling system into the list of your dream home options.

Most people are aware that there are continuous security issues with Microsoft’s Windows operating system and other programs. However
what most people do not realize is how easy it is to significantly improve your computer’s security and reduce the likelihood of becoming a victim to ever increasingly sophisticated threats that lurk on the internet. These steps should take less than a couple of hours to complete and should not clean out your wallet.

1) Windows Update – the first crucial step you need to take to make sure that all your Microsoft applications have all the latest product updates installed. These updates or “patches” address security vulnerabilities and other issues. Microsoft usually issues these updates on a monthly cycle. Visit the Microsoft website or switch on automatic updates from the Windows Control panel. Even if your “new” computer is second hand this is still a critical first step. If you buy a used computer with Windows XP make sure Service Pack 2 or SP2 is installed.

2) Strong Passwords - people often overlook this but having well thought through passwords is an important element of your computer security. A strong password should include at least 8 characters with a mixture of text
symbols and numbers. As a minimum you need to make sure the services most at risk have a strong log-in password. These services include your bank
credit card
other financial services like PayPal
your email address and any other services like Ebay which hackers can use to generate profit.

3) Anti Virus Protection – while it is fair to say the threat of the computer virus has receded during the last couple of years they can still inflict serious damage on your computer. Part of the reason why the threat has reduced is because PC manufactures are now more frequently bundling anti virus packages with their new computers. For example last year my new Dell shipped with a 90-day trial of McAfee's Internet Security Suite. The best bet here is to purchase a security package which includes firewall and anti virus software as a minimum. Top brands include McAfee and Symantec Norton products. However
Microsoft has recently entered the market with their "OneCare" offering which is very aggressively priced.

4) Firewall - if you are using a broadband connection then a firewall is definite requirement to manage the traffic flowing between your computer and the internet. A firewall monitors the inbound internet traffic passing through the ports of your computer. Better products also monitor outbound traffic from your computer to the internet. As per above the best bet here is buy a firewall application as part of a security package which most vendors offer as standard. If a hardware firewall is included as part of your router package then you do not need anything else. A company called Zone Labs offer a great free firewall product called Zone Alarm which should be used as a minimum. Windows XP does now ship with a free firewall but the product does not monitor outbound communication and therefore I believe does not offer adequate protection.

5) Anti Spyware Tool - this software is the last piece in your basic internet security set up. This tool helps combat spyware and adware. There is a good mixture of free and paid versions on offer. Good free software include Microsoft's Windows Defender
Spybot S&D or Ewido Anti-Malware. Ewido Anti-Malware is frequently recommended in computer help forums. Be careful if you decide to purchase a solution. There are a number of rogue vendors out there which aggressively push products which offer you little value. Stick to trusted names like Webroot's Spy Sweeper or PC Tool's Spyware Doctor. These products always come out well on independent tests.